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		ZeroAssoluto
 
 
  Joined: 05 Feb 2017 Posts: 1020 Location: Rimini, Italy
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				 Posted: Sun Jun 12, 2022 10:04 am    Post subject: Jun 12 VH | 
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				Hi everyone, 
 
 
 	  | Code: | 	 		  
 
+--------------+-----------+------------+
 
| 4    28  16  | 7   19 3  | 28  159 56 |
 
| 16   23  7   | 169 5  8  | 23  19  4  |
 
| 58   358 9   | 16  2  4  | 138 7   36 |
 
+--------------+-----------+------------+
 
| 9    6   8   | 2   4  7  | 5   3   1  |
 
| 3    7   5   | 8   19 19 | 4   6   2  |
 
| 2    1   4   | 3   6  5  | 9   8   7  |
 
+--------------+-----------+------------+
 
| 7    4   12  | 159 3  19 | 6   125 8  |
 
| 15   9   123 | 4   8  6  | 7   125 35 |
 
| 1568 58  136 | 15  7  2  | 13  4   9  |
 
+--------------+-----------+------------+
 
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Play this puzzle online at the Daily Sudoku site
 
 
 	  | Quote: | 	 		  W-Wing 
 
1,9 r1c5,r2c8 SL with number 1 in r3c47 and -9 in r1c8,r2c4
 
1,9 r1c5,r2c8 SL with number 1 in r1c3,r2c1 and -9 in r1c8,r2c4
 
1,6 r1c3,r3c4 SL with number 6 in r2c14 and -1 in r1c5
 
1,6 r1c3,r3c4 SL with number 6 in r13c9 and -1 in r1c5
 
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Ciao Gianni | 
			 
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		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
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				 Posted: Sun Jun 12, 2022 10:38 am    Post subject:  | 
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				Another one-step solution is a=5 to solve
 
 	  | Code: | 	 		  
 
+---------------+------------+--------------+
 
| 4    28  e16  |  7   19 3  |  28  159 d56 |
 
| 16   23   7   |  169 5  8  |  23  19   4  |
 
| 58   358  9   |  16  2  4  |  138 7    36 |
 
+---------------+------------+--------------+
 
| 9    6    8   |  2   4  7  |  5   3    1  |
 
| 3    7    5   |  8   19 19 |  4   6    2  |
 
| 2    1    4   |  3   6  5  |  9   8    7  |
 
+---------------+------------+--------------+
 
| 7    4    12  |  159 3  19 |  6   125  8  |
 
| 15   9    123 |  4   8  6  |  7   125 c35 |
 
| 1568 58   136 | a15  7  2  | b13  4    9  |
 
+---------------+------------+--------------+
 
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If a=1 then follow the chain to make e=1 leaving no room for <1> in box 2 | 
			 
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		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
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				 Posted: Sun Jun 12, 2022 10:44 am    Post subject:  | 
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				| Gianni, aren't these VH puzzles meant to be solvable with X, XY or XYZ wings? | 
			 
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		ZeroAssoluto
 
 
  Joined: 05 Feb 2017 Posts: 1020 Location: Rimini, Italy
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				 Posted: Sun Jun 12, 2022 12:22 pm    Post subject:  | 
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				Hi TomC 
 
 
Not sure. 
 
Maybe yes, but not always in one step, as in this case. 
 
 
Ciao Gianni | 
			 
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		dongrave
 
 
  Joined: 06 Mar 2014 Posts: 572
 
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				 Posted: Sun Jun 12, 2022 1:46 pm    Post subject:  | 
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				 	  | TomC wrote: | 	 		  | Gianni, aren't these VH puzzles meant to be solvable with X, XY or XYZ wings? | 	  
 
 
Yes Tom!  Marty told me years ago that all VH puzzles on this site can be solved using just the 3 wings that you mentioned.  Marty coined these solutions as 'Standard Solutions' (since they only use 'Standard' VH moves).  This one looks like it requires 3 standard VH moves.  There's a 35-1 XY-Wing with pivot at r8c9 which removes the 1's from r8c8 and r9c13.  That opens up an X-Wing on 1's in rows 3 and 9 which removes the 1 from r2c4.  That opens up a 19-6 XY-Wing with pivot at r1c5 (and also a 69-1 XY-Wing with pivot at r2c4) which solves the puzzle. | 
			 
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		TomC
 
 
  Joined: 30 Oct 2020 Posts: 359 Location: Wales
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				 Posted: Sun Jun 12, 2022 2:13 pm    Post subject:  | 
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				Thanks, dongrave! I can solve these puzzles in my usual way, but if I know that wings can be used I try that as well.
 
 
I kicked off with the 35-1 XY as you say, then a 15-2 XY but missed the X wing completely so didn't get any further!
 
 
Like you say, multiple steps are not better or worse than a one stepper! | 
			 
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		Mogulmeister
 
 
  Joined: 03 May 2007 Posts: 1151
 
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				 Posted: Sun Jun 12, 2022 2:35 pm    Post subject:  | 
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				| Absolutely. I think getting to understand different solving techniques is more important than step count. Variety is also the spice of sudoku life imho. | 
			 
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